# Linear Solvers and Krylov Methods (KSP)

The `KSP` class provides an easy-to-use interface to the combination of
a Krylov subspace iterative method and a preconditioner `PC` for the solution of linear systems and some least squares problems. See
`PETSCREGRESSORLINEAR` for additional regression (least squares) solvers.


<A HREF="../../../../../src/ksp/ksp/tutorials/index.html">Examples</A><BR>


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<p>
Source files
<p><a href="cgeig.c.html">cgeig.c</a><br>
<a href="cgls.c.html">cgls.c</a><br>
<a href="cgtype.c.html">cgtype.c</a><br>
<a href="cg.c.html">cg.c</a><br>
<a href="cgimpl.h.html">cgimpl.h</a><br>

<p>
Directories
<p><a href="pipeprcg/index.html">pipeprcg</a><br>
<a href="stcg/index.html">stcg</a><br>
<a href="pipecgrr/index.html">pipecgrr</a><br>
<a href="cgne/index.html">cgne</a><br>
<a href="groppcg/index.html">groppcg</a><br>
<a href="pipecg/index.html">pipecg</a><br>
<a href="pipelcg/index.html">pipelcg</a><br>
<a href="nash/index.html">nash</a><br>
<a href="gltr/index.html">gltr</a><br>
<a href="pipecg2/index.html">pipecg2</a><br>